Live images of an ancient "solar clock" have been beamed to a global audience from an ancient tomb in Ireland.

Newgrange: Pic: Knowth.com

For five days around the 21 December winter solstice - the
shortest day of the year - the sun shines deep into a tomb in
County Meath, flooding the chamber with light.

The Newgrange tomb, now one of Ireland's top tourist
attractions, dates to about 3200 BC - 1,000 years before Britain's
Stonehenge was built and 500 years before Egypt's Great Pyramid of
Giza.

For the first time, the phenomenon was streamed live on the
internet.

Speaking before the event, Claire Tuffy, manager of Newgrange, said she was delighted it would be a clear sunrise, because without a midwinter sun the solstice "clock" would not
work.

"It is quite a leap of faith for some international visitors to
travel thousands of miles to get here on the off-chance
of clear skies. It is a big commitment time-wise and financially," she said.

"But people don't really care about the weather. It is the
anticipation that is the most exciting part of the event."

This year, a record 28,106 people from around the world applied
to be one of the 50 lucky people allowed into Newgrange's cramped
chamber, on one of the five days surrounding the solstice.

They travelled from the United States, Canada, Italy,
Switzerland, Australia, Poland and Britain for the experience.

The prehistoric tomb was carefully aligned by its Neolithic
builders so the sun only cuts through the gloom of the chamber at
sunrise through a small window above the entrance.

When skies are clear, the rising sun slowly shines all the way
down the 19-metre long chamber into the centre of the tomb, lighting
it for up to 17 minutes before the rays disappear and darkness
returns.

Excitement

The sun lights up where the cremated ashes of the dead were laid
on large stone basins deep inside the tomb.

Ms Tuffy added: "I was speaking to two women from Yorkshire who told me they were unable to sleep the night
before because they were so excited.

"They kept calling each other in
the night. It is a bit like waiting for Santa Claus."

Newgrange is believed to be the world's oldest continuously
roofed building.

When the tomb's solstice phenomenon was discovered in 1967,
archaeologists were astonished Stone Age builders had the
architectural skills and scientific understanding of the sun's
movement that was needed to construct it.

The grass-roofed tomb is about 13 metres high and 85 metres in
diameter, and covers almost half a hectare.